# Tag Info

## New answers tagged plasma-physics

3

The refractive index comes, mostly, from the electric polarizability of the medium: that is, the amount of electric dipole induced in the medium by a unit driving electric field. This is a macroscopic quantity, calculated by adding up the contributions of each microscopic components, and if you have multiple species in the medium (such as neutral atoms and ...

1

There is no such thing as refractive index of electrons or ions. Although @honeste_vivere has given a very detailed answer but I am answering again thinking that his answer is too much for you. When the electromagnetic radiation interact with plasma the electrons respond quickly and ions are too slow. The plasma refractive index is $$n=\sqrt{\left(1-\frac{... 3 Cold Plasma Index of Refraction We start by deriving the expression for the dielectric tensor, as shown at http://physics.stackexchange.com/a/138460/59023. If we consider the case of a cold uniform plasma with only linear waves, then one can show the dielectric tensor has the form:$$ \begin{align} \overleftrightarrow{\mathbf{K}} & = \left[ \begin{...

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when you put the Maxwell equation in the vlasov equation, you calculate the averages and that is how the terms $\left\langle \frac{\partial f}{\partial t}\right\rangle =0$ since the distribution is not dependent on time and $\left\langle v.\nabla f\right\rangle =0$ because distribution is uniform on an average. similarly if you differentiate the third ...

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df/dt is 0 for stationary condition. but that distribution function is for molecules. Without any charge or potential. However, in your third term you have dependence on intensity and charge, therefore, I suppose, your MB equation should have term for some potential in exponent. Electric or electrostatic. In case of electrostatic, then df/dt = 0. maxwell-...

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A property of the Vlasov equation is that any distribution that is only a function of constants of motion is its solution. So if the velocity of the case you present is not a function of time, the distribution would trivially be a solution of Vlasov.

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In my understanding the reason for using helium first is slightly different: It is correct that helium provides a safe way to start an experiment but safe in that sense that when you use hydrogen you usually have a problem with recycling and refuelling from the wall (hydrogen being bounded to some wall materials, leaves the wall-material, called desorption). ...

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I know this question is a couple years old, but I wanted to provide some cryptanalysis on your question. I am not a cryptographer, but I am a mathematician and computer scientist, so perhaps I can provide some insight. Plasma globes can provide quantum randomness, due to the ionized gas trapped in the globe. Due to Heisenberg's uncertainty principle, the ...

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Your intuition is not right that merely specifying the charge distribution as a function of time is enough to determine the current. Here's a thought experiment to show that: suppose you had an infinite line of perfectly uniform (let's say positive) charge. It would produce an electric field pointing away from the line and no magnetic field. Now imagine ...

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Let's first look at the system up close. I will show you why Ohm's law has nothing to do with the picture you describe, how it emerges and when is applicable. Setup For simplicity let's have a charged fluid flowing at some constant velocity $v$. Your question is formulated in terms of rotation, but we always can look close enough such that it is not ...

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Would there be an electric current given that for any given portion of fluid that moves over another part of the fluid moves to fill the gap left behind and so there is no net change in charge at any given point in space? What you are describing is loosely related to a plasma approximation called magnetohydrodynamics or MHD. Plasmas are highly conductive ...

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A flame has many charged particles (ions and electrons) within it. THose with the appropriate sign are attracted to a charged object and neutralise it. There is a standard demonstration to show that there are charges of both signs within a flame. A candle is placed between two vertical conducting plates which have a potential difference of about 1000 V ...

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